Steven Thomas was not on the ride himself Sunday night. But his daughters and nieces were in the boat just ahead of the one that would be part of the accident.
His wife was recording as the girls' boat rounded a corner. The video shows a section of railing appearing to be loose during the ride.
"When my daughters came off that ride, with my nieces, they described it as being kind of a jolt and they thought their boat was going to flip over," Thomas told Action News on Tuesday.
Thomas said his wife saw the boat hit the railing, but did not notice anything unusual at the time. Their daughters and nieces were not injured and were able to get off the ride safely.
The family only realized the railing moved during the ride when they watched the video.
"When my daughters hit it, my nieces hit it, they got off the ride and said something wasn't right. They had hit something that caused the boat to what they felt was going to flip over," Thomas said.
It did not flip over, but two people in the boat that followed Thomas' family were injured when theirs tipped at an angle.
RELATED: Log flume ride malfunctions at Six Flags Great Adventure, 2 taken to hospital
In a statement to Action News, Six Flags said the two riders were taken to the hospital for further evaluation.
The park said first aid staff assisted those who were stuck on the ride.
"The safety of our guests and employees is our highest priority," Six Flags said.
Thomas said he didn't see that boat hit the railing, but saw what happened afterwards. He said the boat was sitting at approximately 45 degrees and saw a woman crying.
"It definitely could have been my children; they were probably less than a minute away from that happening to them," Thomas said.
Despite the close call, Thomas said he and his family would definitely go on the ride again.
"I've been at Great Adventure a handful of times in my life. I remember going on the log flume 30 years ago and it being one of the great rides there," Thomas said. "I would get on it tomorrow if it was opened it. It's not one of the most extreme rides. It's one of the easier rides."
Park officials said the log flume will remain closed until a full inspection is conducted.